Comparison of Success of Endodontic Treatment in Primary Mandibular Molars Restored with Zirconia and Bulk-fill Composite Resins: A Split-mouth Randomized Clinical Trial.

Background: In recent decades, parents are highly concerned for improving the cosmetic effectiveness of primary teeth restorations. Aim: To assess and evaluate the success of the endodontic treatment in primary mandibular molars restored with zirconia crown and bulk-filled (BF) composite resins. Materials and methods: In this split-mouth randomized controlled trial, 25 children aged 4-8-year-old were randomized into zirconia and BF groups. The endodontic treatment success and survival of restorations were evaluated using Kaplan-Meier and Cox regression analysis. Results: Survival rate was 88% in zirconia and 84% in BF for interradicular radiolucency, and the survival rate was 92% in zirconia and 88% in BF for periapical radiolucency. The survival rate difference between the two categories was 4% in both groups. The assumed noninferiority margin was 15%; according to that, in terms of endodontic success, the BF method was noninferior to the zirconia crown. The study failed to show the noninferiority of BF in terms of survival of restorations. Conclusion: The survival rate of endodontic treatment of BF was noninferior to zirconia, so BF can be considered as a postendodontic esthetic restoration in coronally restorable teeth. Clinical significance: (1) BF composite resin can be used as a postendodontic restoration to satisfy the esthetic demand in developing countries like India. (2) Failure in BF restorations can lead to inadequacy in endodontic treatment. How to cite this article: Zacharia NA, Paulindraraj S, Ramkumar H, et al. Comparison of Success of Endodontic Treatment in Primary Mandibular Molars Restored with Zirconia and Bulk-fill Composite Resins: A Split-mouth Randomized Clinical Trial. Int J Clin Pediatr Dent 2025;18(7):831-837.